The fabrication of semiconductor wafers can include the use of an etching process. An etching process is utilized to remove materials from the surface of a semiconductor wafer, or from films deposited on the wafer, through exposure to a highly reactive chemical species present in an etch reactor. Through the etch process, selected materials are removed from the wafer or film, which shapes the profile and critical dimensions of the remaining materials. The material remaining on the semiconductor wafer can thus become, for example, an operating transistor component, or be used to wire transistors together and thereby produce a functional semiconductor device.
The chemical reactions taking place during the etch process can release various gaseous byproducts into the etch reactor, e.g. aluminum chloride and/or boron oxide. In order to remove these gaseous byproducts, the etch reactor is typically in fluid communication with a device such as a wet scrubber. In particular, the effluent from the etch process which contains the gaseous by products is advanced from the etch reactor to the wet scrubber via a number of pipes. The wet scrubber then removes the byproducts from the etch process effluent. However, a problem with the above described arrangement is that some gaseous byproducts contained in the effluent can precipitate out in the pipes prior to reaching the wet scrubber. This precipitation can obstruct the pipes and thus prevent effluent from reaching the wet scrubber. Therefore, the etching process must be stopped and the pipes cleaned out before additional etching can take place. Stopping the etching process and cleaning the pipes is time consuming and expensive and thus decreases the efficiency of semiconductor wafer fabrication.
An additional problem with the above described arrangement is that many scrubbers are fabricated from stainless steel components and the etch process effluent tends to corrode these components. Therefore, after a certain amount of time these scrubbers must be replaced. The replacement of these scrubbers is also time consuming and expensive and thus further decreases the efficiency of semiconductor wafer fabrication.
Thus, a continuing need exists for an arrangement and method for abating effluent from an etching process which address one or more of the above described problems.